Effect of epitaxial strain on the magneto-electric coupling of YMnO3 thin films

TL;DR

This study investigates how epitaxial strain influences the magneto-electric coupling in YMnO3 thin films, revealing strain-induced modifications in dielectric and magnetocapacitive properties, with potential for tuning multiferroic behavior.

Contribution

It demonstrates that epitaxial strain can be used to modulate the magneto-electric coupling in YMnO3 thin films, providing a new approach to control multiferroic properties.

Findings

Dielectric anomaly near 30 K influenced by strain

Enhanced magnetocapacitance with magnetic field parallel to ab plane

Strain tuning of multiferroic properties demonstrated

Abstract

We report synthesis of phase pure multiferroic YMnO3 thin films on sapphire (0001)with conducting ZnGaO buffer contact layer. Films were prepared by using pulsed laser deposition technique and characterized using x-ray diffraction(XRD), Scanning electron microscopy (SEM), Energy dispersive absorption spectroscopy (EDAX) and magnetic field dependent dielectric measurement techniques. Structural characterizations indicated phase purity and epitaxial nature of the films. The dielectric response indicated an anomaly in dielectric constant and tand in the vicinity of 30 K, well below the bulk Neel temperature ~ 70 K. This anomaly in dielectric constant and tand and its magnetic field dependence is explained as an influence of strain due to lattice mismatch between the substrate and YMnO3 film. A substantial enhancement in magnetocapacitance was also observed for magnetic field applied parallel to ab plane of the film. Our results show that it is possible to tune the multiferroic property of YMnO3 via changes in ferroelastic route.